:type root: TreeNode :rtype: bool
(self, root)
| 41 | |
| 42 | class Solution(object): |
| 43 | def isSymmetric(self, root): |
| 44 | """ |
| 45 | :type root: TreeNode |
| 46 | :rtype: bool |
| 47 | """ |
| 48 | if not root: |
| 49 | return True |
| 50 | |
| 51 | left = root.left |
| 52 | right = root.right |
| 53 | |
| 54 | left_node = [left] |
| 55 | right_node = [right] |
| 56 | |
| 57 | left_node_value = [] |
| 58 | |
| 59 | while left_node: |
| 60 | # if left_node: |
| 61 | _left = left_node.pop() |
| 62 | if _left: |
| 63 | left_node_value.append(_left.val) |
| 64 | else: |
| 65 | left_node_value.append(None) |
| 66 | |
| 67 | if _left: |
| 68 | left_node.append(_left.right) |
| 69 | left_node.append(_left.left) |
| 70 | |
| 71 | left_node_value.reverse() |
| 72 | |
| 73 | while right_node: |
| 74 | _right = right_node.pop() |
| 75 | |
| 76 | if left_node_value: |
| 77 | left_value = left_node_value.pop() |
| 78 | else: |
| 79 | return False |
| 80 | |
| 81 | if _right: |
| 82 | if left_value != _right.val: |
| 83 | return False |
| 84 | else: |
| 85 | if left_value != None: |
| 86 | return False |
| 87 | |
| 88 | if _right: |
| 89 | right_node.append(_right.left) |
| 90 | right_node.append(_right.right) |
| 91 | return True |